1. Field of the Invention
This invention relates to a gas powered pressureless steam cooker, especially to a gas powered steamer for commercial or restaurant use. The term "pressureless steam cooker" is intended to mean a steam cooker in which no great pressure of steam is developed although minor pressure of say 1/2 lb. per square inch may be permissible.
2. Acknowledgement of Prior Art
Steam cookers conventionally cook foods by the use of hot steam and may be powered by a steam generator which is either gas fired or electrical fired. No electric heating elements are present in the cooking compartment itself. For gas fired units, there has always been an ongoing problem in providing steam at a suitable temperature inside the cooking compartment without the loss of efficiency, e.g. heat in delivering the steam to the cooking compartment. For pressureless steam cookers steam is generally supplied into the cooking compartment through an open vent thus allowing ingress of wet steam at low temperatures.
The common design of a steam generator, or heat exchanger, up to today utilizes an atmospheric burner heating the outside of a steam generator. Atmospheric style burners are generally larger and have low efficiency due to their operating characteristics of burning in the open atmosphere. Usually such steam generators are located below the oven compartment but in some cases oven compartments are side-by-side with steam generators.
Examples of steam ovens are shown in:
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